When people refer to “biological clock,” they are usually referring to something else. It’s mostly associated with women having the urge to get pregnant near the end of their child bearing years.
What you’re referring to is circadian rhythm. Life on earth has evolved around a 24 hour cycle, and whether we are conscious of it or not we know when to expect daylight and other things.
https://en.m.wikipedia.org/wiki/Circadian_rhythm
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